Hand Tools

Home-Made Portable Mortising Machine

I can’t decide whether this guy is a genius or a wacko with too much time on his hands. I’m leaning towards genius…

He’s a Russian carpenter named Alex K. and he built a machine that does the same thing as a Festool Domino. It’s made from a Bosch Colt router and what looks to be about 300 rubles ($10) worth of plywood and hardware. In case you’re not familiar with the Domino, it’s a highly precise hand-held machine that cuts mortises for loose tenons. The smaller model sells for about $800 and the larger model for about $1,200. That may explain why Alex decided to make his own.

The video below is on the long side, which is to be expected given that the inventor has to explain without words (to those of us who do not speak Russian) how he built a simple tool that does something so complicated.

Highlights include:
1:10 installing the router
210 flipping the router over for left-hand use
4:35 connecting the hose for dust collection (yeah, this thing even has a dust collection port)
5:30 demonstrating the stop which controls depth-of-plunge
6:10 the bungee that pulls the router back at the end of the cut
6:40 adjusting the fence
9:50 showing the bevel scale

Here’s where it gets interesting:
10:47 Inventor points to the adjustable bolt the controls the width of the mortise. At this point it’s as far back as it will go, so the tool can only plunge straight forward and make a circular hole
10:50 if you move the bolt forward, to where there is more space between the v-shaped guides, the router can swing side to side and create a wider mortise.
11:15 inventor moves the bolt forward to adjust the throw of the tool — and thereby, the width of the mortise; the farther forward he moves it the wider the mortise will be
12:00 shows straight plunge used to drill dowel holes
12:45 inventor shows how the bit can be moved side-to-side (after moving the adjustment bolt forward) to cut a mortise wide enough to accept a Domino tenon.

After watching the video multiple times I’m starting to think I’d rather spend $800 for a Domino than have to build one of these things. But that’s just me. If you are dying to have a tool of this type and cannot afford to buy one, Alex sells plans for $11 on his blog page. The page is in Russian but you can view it in English by opening the URL in the Google Chrome browser and hitting the button at the top that says translate.